D.
BARUTZKI

Veterinary Laboratory Freiburg, 79111 Freiburg i.Br., Germany

ABSTRACT

Flagellates of the genus Giardia are
ubiquitous in their distribution and found in the intestinal tract of humans
and animals of several species throughout the world. The prevalence data in
dogs and cats quoted in the literature indicate that the incidence of Giardia
spp. varies considerably and depends to a large extend on the methods used and
the composition of the studied population. The objective of the study presented
was to determine the prevalence of Giardia infections in dogs and cats
in Germany.

Between January 1998 and March 2001 fecal
samples of 6534 dogs and 2234 cats were examined for the presence of Giardia.
All fecal samples were obtained from private-owned dogs or cats presented at
local veterinary practitioner for either a medical problem, or for routine
examination and vaccination. The specimen were examined for Giardia-specific
antigen by means of the coproantigen test ProSpectTÒGiardia Micoplate Assay or for cysts of Giardia
by means of MIFC (Merthiolate-Iodine-Formaldehyd-Concentration) technique. The
evaluation of the coproscopical examination showed 14.0 % Giardia
positive dogs in the year 1998, 16.7 % in 1999, 20.5 % in 2000 and 23.7 % in
2001. A total of 1150 of 6534 dogs (17.6 %) were proved to be infected with Giardia
spp. The evaluation of the cat data revealed 6.5 % positive cats in the year
1998, 7.9 % in 1999, 13.9 % in 2000 and 14.7 % in 2001. The average prevalence
over the 4-year period was 10.2 %.

KEYWORDS

Giardia,
dog, cat, prevalence, Germany

INTRODUCTION

Giardia are
ubiquitous in their distribution, but the following examples of prevalences
data in dogs in Germany of 3.5 % (Jungmann et al. 1986) and 6.0 % (Epe et al.
1993), in Switzerland of 1.6 % (Wolff and Eckert 1979) and 6.5 % (Seiler et al.
1983), in Austria of 15.3 % (Pfeiffer and Supperer 1976) and in the United
States of 7.2 % up to 100 % (Kirkpatrick 1988) as well as in cats in Germany of
1.4 % (Beelitz et al. 1992) and 2.4 % (Epe et al. 1993) and in the United
States of 3.5 % (Kirkpatrick 1988) indicate that the incidence of these
flagellates varies considerably and depends to a large extent on the
composition of the studied population. Major parameters which influence the
spread of Giardia are the age of the dogs concerned (Pfeiffer and
Supperer 1976, Wolff and Eckert 1979, Seiler et al. 1983, Swan and Thompson
1986) followed by the management system, colony size and breeding frequency
(Kirkpatrick 1988). Although many studies on the prevalence of Giardia
have been reported, there are only few epidemiological surveys conducted in
Germany. The objective of the study presented was to determine the prevalence
of Giardia infections in dogs and cats in Germany.

MATERIALS AND METHODS

Between January 1998 and March 2001 fecal
samples of 6534 dogs and 2234 cats were examined for the presence of Giardia.
All fecal samples were obtained from private-owned dogs presented at local veterinary
practitioners for ether a medical problem or for routine examination and
vaccination. The specimen were examined for Giardia-specific antigen by
means of the coproantigen test ProSpectTÒGiardia Micoplate Assay or for cysts of Giardia
by means of MIFC (Merthiolate-Iodine-Formaldehyde-Concentration) technique.

Coproantigen test

ProSpectTÒGiardia Micoplate Assay is a solid phase
immunoassay for the detection of Giardia Specific Antigen (GSA 65).
Diluted fecal specimens are added to microplate wells on which anti-GSA 65
antibody is bound. Present GSA 65 is fixed to the bound antibody. After
inoculation and washing a monoclonal anti-GSA antibody labelled with
horseradish peroxidase enzyme is added. The wells are incubated and then washed
to remove unbound enzyme conjugate. The substrate for the enzyme (TMB) is added
and the colored reaction can be detected visually or spectrophotometrically.

MIFC technique

According to the method developed by Sapero and
Lawless (1953) and modified by Blagg et al. (1955) MIF
(Merthiolate-Iodine-Formaldehyde) preserved fecal specimens are strained
through gauze, shaked with ether and then centrifuged. After pouring off the
ether layer, the plug of fecal detritus, and the MIF layer cysts of Giardia
can be found by microscopically examination of the sediment.

RESULTS

The evaluation of the coproscopical examination
showed 14.0 % Giardia positive dogs in the year 1998, 16.7 % in 1999,
20.5 % in 2000 and 23.7 % in 2001. A total of 1150 of 6534 dogs (17.6 %) were
proved to be infected with Giardia spp. (Table 1).

Table 1. Prevalence of Giardia in dogs determined by fecal analysis

Year

Number of dogs tested

Number of Giardiapositive
dogs

Percentage (%) of Giardia
positive dogs

1998

1892

264

14.0

1999

2139

358

16.7

2000

2018

413

20.5

2001

485

115

23.7

Total

6534

1150

17.6

The evaluation of the cat data revealed 6.5 %
positive cats in the year 1998, 7.9 % in 1999, 13.9 % in 2000 and 14.7 % in
2001 (Table 2). The average prevalence over the 4-year period was 10.2 %.

Table 2. Prevalence of Giardia in cats determined by fecal analysis

Year

Number of cats tested

Number of Giardiapositive
cats

Percentage (%) of Giardia
positive cats

1998

506

33

6.5

1999

775

61

7.9

2000

762

106

13.9

2001

191

28

14.7

Total

2234

228

10.2

With reference to 845 Giardia positive
dogs and 170 positive cats with known age the rate of infection with respect to
age of the animals showed distinctly higher values in puppies and kittens compared
to older animals (Table 3). 70.2 % of the infected dogs and 75.3 % of the
infected cats were up to 1 year old, 11.8 % and 11.2 % were between 1 and 2
years old, 5.1 % and 2.9 % were between 2 and 3 years old, and 2.7 % and 1.2 %
were between 3 and 4 years old, respectively. The percentages of the dogs and
cats older than 4 years ranged between 0 % and 1.8 % and between 0 % and 3.5 %,
respectively.

Table 3. Structure of age of Giardia positive
dogs and cats

Age
of the Giardia positive dogs and cats

Number
of Giardia positive dogs

Percentage
(%) of Giardia positive dogs

Number
of Giardia positive cats

Percentage
(%) of Giardia positive cats

Up to 1 year

593

70.2

128

75.3

>1 - 2 years

100

11.8

19

11.2

>2 - 3 years

43

5.1

5

2.9

>3 - 4 years

23

2.7

2

1.2

>4 - 5 years

15

1.8

6

3.5

>5 - 6 years

11

1.3

3

1.8

>6 - 7 years

8

0.9

2

1.2

>7 - 8 years

13

1.5

1

0.6

>8 - 9 years

8

0.9

1

0.6

>9 - 10
years

7

0.8

2

1.2

>10 - 11
years

8

0.9

1

0.6

>11 - 12
years

3

0.4

0

0

>12 - 13
years

6

0.7

0

0

>13 - 14 years

4

0.5

0

0

>14 - 15
years

1

0.1

0

0

>15 - 16
years

1

0.1

0

0

>16 - 17 years

0

0

0

0

>17 - 18 years

1

0.1

0

0

Total

845

100,0

170

100,0

CONCLUSION

The results of the study indicate a high percentage of pet dogs
(17.6 %) and cats (10.2 %) in Germany being infected with Giardia.

The prevalence of Giardia in dogs and cats in Germany is
higher than reported by former surveys conducted in Germany.

Infections with Giardia occur more often in puppies and
kittens than in adult dogs and adult cats.

Feces of pet dogs and cats should be periodically examined for Giardia
by of means of coproantigen test or MIFC technique.

Treatment of all dogs and cats infected with Giardia is
recommended to cure acute symptoms of giardiasis, to avoid reinfections,
and to reduce the potential zoonotic risc for man.

LITERATURE CITED

Beelitz,
P., E. Goebel, and R. Gothe 1992. Fauna and incidence of endoparasites in
kittens and their mothers from different husbandry situations in south Germany.
Tieraerztl. Prax. 20: 297-300.